1. Field of the Invention
The invention relates to organopolysiloxanes and to a process for preparing them.
EP 1037 937 B1 discloses processes for preparing organopolysiloxanes which contain structural units in which two R2Si units are joined to one another via a difunctional α,ω-alkanediyl radical having 2 to 18 C atoms.
2. Description of the Related Art
EP 868 470 B1 describes organopolysiloxanes having aliphatically unsaturated radicals which include at least one unit of the formula O1/2R2SiOxYRSiO and also, where appropriate, O1/2R2SiOxYR2SiO1/2 units. In the case of “x”=0 either a dialkylsiloxy unit is joined to an alkylsiloxy unit and/or two dialkylsiloxy units are joined to one another via the spacer Y. Y is a difunctional radical of the formula —(CR32)nCHR3—, with R3 being an aliphatically saturated hydrocarbon radical or being H, and n being zero or an integer from 1 to 7. Siloxane polymers with a spacer O1/2R2SiYRSiO are also described in U.S. Pat. No. 4,886,865.
Organopolysiloxane compounds with active hydrogen in the form of H—Si compounds and also hydrocarbon bridges between two Si atoms are described in EP 786 463 A1 and also JP 06 107 949 and U.S. Pat. No. 4,849,491.